Choose a version:
31% The original file has 282550 bytes (275.9k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 86411 bytes (84.4k, 31%).

After GZIP compression these minified files vary in size:
Boot
  36096 bytes (35.3k)
CDN
cdnjs
  31753 bytes (31.0k)
CDN
gzip -6 (default)
  31569 bytes (30.8k)
local copy
unpkg
  31532 bytes (30.8k)
CDN
gzip -9
  31516 bytes (30.8k)
local copy
libdeflate -12
  30541 bytes (29.8k)
local copy
7zip -mx=9 -tgzip
  30497 bytes (29.8k)
local copy
kzip -s0 -rn -b3
  30490 bytes (29.8k)
local copy
pigz -11 -n
  30444 bytes (29.7k)
local copy
Zopfli
  30391 bytes (29.7k)
local copy
Zopfli (defluff)
  30390 bytes (29.7k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/vue/vue-2.5.6.min.js

You will automatically get the smallest Vue 2.5.6 file, ETag caching is available and
if your browser doesn't support GZIP decompression then the uncompressed version will be sent.

Currently best Zopfli settings

Save 1141 bytes by using my Vue 2.5.6 Zopfli version instead of the best available CDN (3.75% smaller than unpkg, 30391 vs. 31532 bytes):
You can use my super-compressed files for whatever purpose you like as long as you respect the library's original license agreement.
There are no restrictions from my side - but please avoid hot-linking if you run a high-traffic website.

These command-line settings yielded the best compression ratio so far (Linux version of zopfli-krzymod):
zopfli --i1000000 --mb8 --mls2 --bsr11 --lazy --ohh

(found November 22, 2017)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 2  --mls2
block splitting recursion 11  --bsr11
lazy matching in LZ77 yes  --lazy
optimized Huffman headers yes  --ohh
initial random W for iterations 1  --rw1
initial random Z for iterations 2  --rz2

Even Smaller Files Thanks To Defluff

Zopfli's output can be further optimized by the defluff tool.
In this particular case, defluff saves 1 more byte (30390 bytes).

Verify file integrity

After decompression, my uncompressed files are identical to the original ones:

MD5:
curl --silent --compressed https://raw.githubusercontent.com/vuejs/vue/vue-2.5.6.min.js --location | md5sum
bc58ee098a3ae00e38948b69cfa0bfd9  -
curl --silent --compressed http://minime.stephan-brumme.com/files/vue/vue-2.5.6.min.zopfli.js.gz | md5sum
bc58ee098a3ae00e38948b69cfa0bfd9  -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/vuejs/vue/vue-2.5.6.min.js --location | sha1sum
2128f0b7d49c148f9f3e0e2e7346d11eb79ac415  -
curl --silent --compressed http://minime.stephan-brumme.com/files/vue/vue-2.5.6.min.zopfli.js.gz | sha1sum
2128f0b7d49c148f9f3e0e2e7346d11eb79ac415  -

All listed CDNs deliver identical contents:
CDN Size (compressed) MD5 (uncompressed) Timestamp
Boot 36096 bytes bc58ee098a3ae00e38948b69cfa0bfd9 November 22, 2017 @ 09:14
cdnjs 31753 bytes bc58ee098a3ae00e38948b69cfa0bfd9 (invalid)
unpkg 31532 bytes bc58ee098a3ae00e38948b69cfa0bfd9 (invalid)

Note: only the MD5 hashes are shown to keep things simple.

Other Versions

Available Vue versions at minime.stephan-brumme.com:

2.5.16, 2.5.15, 2.5.14, 2.5.13, 2.5.12, 2.5.11, 2.5.10, 2.5.9, 2.5.8, 2.5.7, 2.5.6, 2.5.5, 2.5.4, 2.5.3, 2.5.2, 2.5.1, 2.5.0, 2.4.4, 2.4.3, 2.4.2, 2.4.1, 2.4.0, 2.3.4, 2.3.3, 2.3.2, 2.3.1, 2.3.0, 2.2.6, 2.2.5, 2.2.4, 2.2.3, 2.2.2, 2.2.1, 2.2.0, 2.1.10, 2.1.9, 2.1.8, 2.1.7, 2.1.6, 2.1.5, 2.1.4, 2.1.3, 2.1.2, 2.1.1, 2.1.0, 2.0.8, 2.0.7, 2.0.6, 2.0.5, 2.0.4, 2.0.3, 2.0.2, 2.0.1, 2.0.0,
1.0.28, 1.0.27, 1.0.26, 1.0.25, 1.0.24, 1.0.23, 1.0.22, 1.0.21, 1.0.20, 1.0.19, 1.0.18, 1.0.17, 1.0.16, 1.0.15, 1.0.14, 1.0.13, 1.0.12, 1.0.11, 1.0.10, 1.0.9,
0.10.6, 0.10.5, 0.10.4, 0.10.3, 0.10.2, 0.10.1, 0.10.0,
0.9.3, 0.9.2, 0.9.1, 0.9.0

The project site contains an overview how well these versions were compressed.
Other interesting projects are AngularJS, BackboneJS, Bootstrap, D3, Dojo, Ember, jQuery, Knockout, lodash, React, Socket.IO, ThreeJS and UnderscoreJS.

Changelog

Best Zopfli parameters so far:
Size Improvement Parameters Found
30391 bytes -1 byte zopfli --i1000000 --mls2 --bsr11 --lazy --ohh November 22, 2017 @ 01:51
30392 bytes -3 bytes zopfli --i100000 --mls2 --bsr11 --lazy --ohh November 21, 2017 @ 15:46
30395 bytes -3 bytes zopfli --i10000 --mls2 --bsr11 --lazy --ohh November 21, 2017 @ 15:19
30398 bytes -7 bytes zopfli --i1000 --mls2 --bsr11 --lazy --ohh November 21, 2017 @ 13:46
30405 bytes zopfli --i100 --mls2 --bsr11 --lazy --ohh November 21, 2017 @ 13:38

If there are multiple parameter sets yielding the same compressed size, only the first one found is shown.

Most recent activity on November 22, 2017 @ 10:28.

Heatmaps

This Zopfli heatmap visualizes how compression changes when modifying the --bsr and --mls parameter.
Cell's contents is the best filesize achieved (in bytes, hover with mouse over cells to see number of iterations).

Good parameters are green, bad are red. The best and worst are bold as well.
The brightness of the blue background color indicates how many iterations were processed:
10,000, 100,000 or 1,000,000.
bsr \ mls
2 4 8 16 32 64 128 256 512 1024 2048 4096 8192 16384 32768
bsr \ mls
2 4 8 16 32 64 128 256 512 1024 2048 4096 8192 16384 32768
30449 30449 30436 30444 30441 30431 30436 30435 30439 30434 30436 30437 30416 30427 30430
30421 30416 30421 30422 30435 30435 30435 30440 30440 30417 30417 30437 30435 30423 30416
30415 30415 30415 30417 30417 30417 30414 30415 30414 30417 30415 30435 30418 30418 30425
30417 30432 30431 30415 30415 30417 30417 30416 30418 30417 30418 30435 30423 30416 30423
30415 30422 30435 30425 30435 30416 30416 30418 30435 30414 30415 30434 30418 30437 30424
30439 30432 30437 30441 30436 30416 30415 30417 30415 30417 30417 30434 30421 30435 30426
30441 30421 30421 30419 30417 30425 30416 30415 30415 30420 30435 30434 30440 30416 30425
30391 30415 30415 30416 30415 30417 30417 30438 30435 30415 30416 30431 30418 30419 30424
30418 30421 30417 30415 30417 30417 30418 30442 30415 30417 30415 30434 30417 30418 30425
30420 30427 30413 30416 30417 30417 30416 30414 30418 30418 30416 30434 30420 30417 30428
30424 30420 30421 30425 30432 30420 30416 30415 30415 30415 30416 30431 30417 30415 30426
30400 30411 30431 30416 30413 30415 30415 30418 30415 30413 30419 30435 30422 30417 30424
30413 30421 30416 30415 30418 30419 30419 30416 30413 30418 30415 30430 30421 30418 30426
30414 30436 30419 30419 30420 30418 30415 30418 30415 30418 30415 30432 30417 30418 30426
30433 30433 30433 30438 30435 30419 30416 30437 30415 30417 30415 30416 30417 30417 30425
30433 30439 30434 30434 30435 30417 30416 30417 30415 30417 30415 30432 30417 30417 30427
30411 30423 30426 30419 30423 30417 30418 30417 30414 30416 30414 30432 30417 30424 30425
30396 30415 30414 30420 30417 30416 30416 30416 30415 30417 30415 30435 30418 30417 30425
30433 30433 30421 30433 30416 30419 30415 30417 30415 30418 30435 30432 30422 30427 30426
30415 30421 30429 30419 30415 30417 30417 30416 30415 30417 30415 30434 30418 30418 30424
30418 30437 30419 30415 30416 30415 30415 30417 30415 30417 30416 30434 30417 30417 30426
30417 30423 30415 30418 30416 30416 30416 30440 30416 30417 30415 30434 30417 30416 30425
30420 30415 30414 30415 30417 30417 30416 30415 30415 30417 30414 30418 30416 30416 30426

Due to the Monte Carlo design of my search algorithm, not all parameters have reached the same number of iterations yet:
Iterations Min. Bytes Reduction Coverage
100 30405 bytes 100%
1,000 30398 bytes -7 bytes 100%
10,000 30395 bytes -3 bytes 100%
100,000 30392 bytes -3 bytes 0.58%
1,000,000 30391 bytes -1 byte 0.29%
10,000,000

KZIP has far less options available for tuning/optimization. I only played around with the number of blocks (parameter -n):
Blocks Min. Bytes Compared To Best Zopfli Compared To Best KZIP
30494 bytes +103 bytes (+0.34%) +4 bytes
30496 bytes +105 bytes (+0.35%) +6 bytes
30512 bytes +121 bytes (+0.40%) +22 bytes
30490 bytes +99 bytes (+0.33%)
30505 bytes +114 bytes (+0.38%) +15 bytes
30538 bytes +147 bytes (+0.48%) +48 bytes
30571 bytes +180 bytes (+0.59%) +81 bytes
30602 bytes +211 bytes (+0.69%) +112 bytes
30621 bytes +230 bytes (+0.76%) +131 bytes

Non-DEFLATE Algorithms

Archivers based on completely different compression algorithms often produce superior results.
Unfortunately, browsers only support gzip compression at the moment.
Algorithm Program Parameters Size Compared To Best Zopfli
ZPAQ (Wikipedia) zpaq zpaq -method 69 24885 bytes -5506 bytes (-18.12%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 25748 bytes -4643 bytes (-15.28%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 26827 bytes -3564 bytes (-11.73%)
Brotli (Wikipedia) brotli brotli -q 11 28312 bytes -2079 bytes (-6.84%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 28861 bytes -1530 bytes (-5.03%)
LZMA2 (Wikipedia) xz xz -9 29052 bytes -1339 bytes (-4.41%)
ZSTD (Wikipedia) zstd zstd -19 29833 bytes -558 bytes (-1.84%)

Detailled Analysis

I wrote a DEFLATE decoder in Javascript. Click the button below to start a client-side analysis of the smallest gzipped files (may take a second):


Notes: pigz is a fast open source multi-threaded implementation of gzip written by one of the original authors of gzip.
However, when using compression level 11, pigz actually switches to the slower Zopfli algorithm and isn't multi-threaded anymore.
KrzyMOD's extensions to Zopfli offer the highest level of configuration and is therefore used for my brute-force search.
Ken Silverman wrote the closed-source KZIP compression program and Jonathon Fowler ported it to Linux.
Defluff was created by Joachim Henke; DeflOpt is a tool by Ben Jos Walbeehm.

website made by Stephan Brumme in 2015 and still improving in 2018.
all timestamps are displayed in central european time. see my changelog.
no flash, not even images or external css files - and everything squeezed into a single html file.
which was handsomely compressed before releasing it into the wild internet - obviously.

please visit my homepage and my blog, too.
email: minime (at) stephan-brumme.com